An iron-based amorphous soft magnetic alloy and a preparation method thereof

Abstract

The present invention provides an iron-based amorphous soft magnetic alloy and a preparation method thereof. The chemical composition of the iron-based amorphous soft magnetic alloy is: Fe a Co b Ni c Si d B e M f , where a, b, c, d, e, and f respectively represent the weight percentage contents of the corresponding elements; 5%

Description

Technical Field

[0001] The present invention belongs to the technical field of magnetic materials, and particularly relates to an iron-based amorphous soft magnetic alloy and a preparation method thereof. Background Art

[0002] The core component of a new type of electric meter is a high-precision current transformer, which plays a key role in high-precision measurement. With the popularization and application of new type of electric meters, the global market demand for precision current transformers is gradually expanding. Currently, the common method for improving the performance of precision current transformers is to change the magnetic characteristics of the magnetic core inside the current transformer to overcome the magnetic saturation caused by the DC component, that is, to prepare an alloy with high linearity and low magnetic permeability to meet the requirements. There are mainly the following methods:

[0003] (1) Increasing the saturation magnetic flux density of the magnetic core or increasing the effective cross-sectional area of the magnetic core to obtain a larger saturation magnetic flux. However, the former is often limited by the intrinsic properties of the material, and the latter is contrary to the development trend of lightweight and miniaturization in the current power electronics field; (2) Using a dual magnetic core to achieve DC bias. This scheme is the main method for current electric meters. CN215220488U discloses a dual magnetic core current transformer structure, and the dual magnetic core current transformer is composed of two parallel or concentric ring-shaped magnetic cores, which respectively have high magnetic permeability and low magnetic permeability. The high magnetic permeability magnetic core can ensure lower ratio error and angular error, while the low magnetic permeability magnetic core has a high saturation magnetic field strength, so it can meet higher DC bias requirements. However, due to the non-constant error, dual magnetic core current transformers are often used in some working occasions with lower precision requirements and relatively stable alternating frequencies, and cannot meet the performance requirements of high-precision current transformers; (3) Achieving DC bias through a low magnetic permeability magnetic core. This type of magnetic core has a low magnetic permeability, so it has a high saturation magnetic field strength and good DC resistance performance. At the same time, it is required that the magnetic permeability is constant, that is, it decays less with the magnetic field strength, and the angular error and ratio error of the current transformer are approximately constant. Therefore, its error can be calibrated through a simple compensation circuit. This method is simple and feasible and is the main research direction of high-precision current transformers.

[0004] At present, the main preparation methods of high linearity and low magnetic permeability magnetic cores are as follows: ① Tension annealing treatment. After annealing, the nanocrystalline alloy has low constant magnetic conductivity characteristics. However, since the alloy is processed in single strips and is prone to brittle fracture, the processing efficiency is low, the production cost is high, and it is difficult to meet large-scale batch applications; ② Adjusting the alloy composition. For example, CN104195436A discloses a low magnetic permeability nanocrystalline soft magnetic alloy and its preparation method. The composition and weight parts of the low magnetic permeability nanocrystalline soft magnetic alloy are as follows: 60-70 parts of iron; 1-5 parts of nickel; 5-10 parts of silicon; 5-10 parts of boron; 5-10 parts of niobium; 0.7-1.3 parts of copper; 1-2 parts of aluminum; 0.1-1.7 parts of cobalt; The magnetic permeability is reduced by changing the magnetostriction coefficient by adjusting the formula and heat treatment process. However, since the above materials are nanocrystalline alloys, the requirement for crystallization control during the heat treatment process is relatively high, and the treatment process is complex. CN102969115A discloses a constant magnetic permeability core material for a DC component resistant current transformer and its preparation method. The constant magnetic permeability core material is made from raw materials of 16-24 wt% of cobalt, 8.5-9.5 wt% of nickel, 2.5-3.5 wt% of manganese, 0.05-0.1 wt% of chromium, 12-14 wt% of silicon, 2.55-2.9 wt% of boron, and 46-58.4 wt% of iron; By adding elements such as chromium and manganese to the iron-cobalt-nickel-based amorphous alloy, a constant magnetic permeability alloy is prepared. However, since the cobalt and nickel contents of this alloy are relatively high, the production cost is high. In addition, a strong magnetic field with an intensity level of tens of thousands of kA / m needs to be introduced during the heat treatment process, which is difficult to achieve in industrial batch production.

[0005] Therefore, it is particularly important to develop an iron-based amorphous soft magnetic alloy with low material cost, simple heat treatment process, and suitable for large-scale industrial production. Summary of the Invention

[0006] Aiming at the deficiencies and defects existing in the prior art, the present invention aims to provide an iron-based amorphous soft magnetic alloy and its preparation method. The present invention adds appropriate amounts of Co and Ni elements to the traditional FeSiB alloy, in combination with other alloy components, to increase the anisotropy and magnetostriction of the amorphous alloy. After that, magnetic field heat treatment is carried out to orient the anisotropy, resulting in an amorphous alloy with constant magnetic permeability / low magnetic permeability. The magnetic permeability of the iron-based amorphous soft magnetic alloy prepared by the present invention is 1000-2000, and the attenuation degree is ≤2% in the magnetic field range of 0-600 A / m, with high linearity. Moreover, the saturation DC magnetic field strength of the iron-based amorphous soft magnetic alloy of the present invention can reach up to 800 A / m at most, effectively suppressing DC saturation; The preparation process of the present invention has a simple material composition, no easily burned components (such as P, C), good fluidity of the molten steel during the rapid quenching process of the material, and the preparation process is greatly simplified by simple magnetic field heat treatment without the need for a strong magnetic field or special atmosphere, and the material cost is low.

[0007] To achieve the above object, the first aspect of the present invention provides an iron-based amorphous soft magnetic alloy, adopting the following technical solution:

[0008] An iron-based amorphous soft magnetic alloy, the chemical composition of the iron-based amorphous soft magnetic alloy being: Fe a Co b Ni c Si d B e M f , where a, b, c, d, e, f respectively represent the weight percentage contents of the corresponding elements; 5% < b < 20% (such as 6%, 9%, 11%, 13%, 15%, 17%, 19%), 10% < c < 20% (such as 10.5%, 12%, 14%, 15%, 17%, 19%, 19.5%), 7% < d < 10% (such as 7.2%, 7.5%, 8%, 8.5%, 9%, 9.5%, 9.8%), 0 < e < 5% (such as 0.5%, 1%, 2%, 2.5%, 3%, 4%, 4.5%), 0 ≤ f < 1% (such as 0.05%, 0.1%, 0.3%, 0.5%, 0.7%, 0.9%, 0.95%), the balance being a, and 20% < b + c < 30% (such as 20.5%, 21%, 23%, 25%, 27%, 29%, 29.5%); M is one or more of Cr, Mo, Mn, V, Al.

[0009] In the iron-based amorphous soft magnetic alloy of the present invention, the Fe element provides the necessary properties of the soft magnetic alloy, the Si and B elements ensure the amorphous formation ability, the addition of the Co element and the Ni element is to adjust the anisotropy of the alloy, and the element composition and content of the soft magnetic alloy are limited within the above range, so that the iron-based amorphous soft magnetic alloy has high linearity and anti-dc saturation ability. In the present invention, too high Co content will increase the cost and reduce the anti-dc saturation ability at the same time, and too low Co content will reduce the anti-dc saturation ability; too high or too low Ni content will reduce the linearity.

[0010] In the present invention, if the Si content is too high, the ability of the soft magnetic alloy to resist DC saturation will be weakened (mainly reflected in the increase of the alloy permeability, which is contrary to the purpose of the invention of this application); if the content of M (one or more of Cr, Mo, Mn, V, Al) is too high, that is, after adding more alloying elements, it will have an impact on the amorphous formation ability, making it more difficult to prepare amorphous alloy strips. At the same time, adding more alloying elements will also make the smelting of alloy steel liquid more difficult, and more precise control is required in terms of vacuum degree, smelting temperature, impurity elements, etc., that is, the cost increases; in the present invention, if only the nickel content is increased and the Co content is decreased, and the usage amounts of other components still adopt the usage amounts in the above-mentioned patent CN102969115A, the DC resistance performance of the obtained alloy will be weakened. At the same time, through experiments, it is found that the Mn element significantly increases the magnetic loss of the material. After reducing the Mn element content in the present invention and further adjusting the Co / Ni element ratio on this basis, the magnetic loss of the alloy can be greatly reduced.

[0011] In the above-mentioned iron-based amorphous soft magnetic alloy, as a preferred embodiment, the chemical composition of the iron-based amorphous soft magnetic alloy is: Fe a Co b Ni c Si d B e , where a, b, c, d, e respectively represent the weight percentage contents of the corresponding elements, 5% < b < 20% (such as 6%, 9%, 11%, 13%, 15%, 17%, 19%), 10% < c < 20% (such as 10.5%, 12%, 14%, 15%, 17%, 19%, 19.5%), 7% < d < 10% (such as 7.2%, 7.5%, 8%, 8.5%, 9%, 9.5%, 9.8%), 0 < e < 5% (such as 0.5%, 1%, 2%, 2.5%, 3%, 4%, 4.5%), and the balance is a, and 20% < b + c < 30% (such as 20.5%, 21%, 23%, 25%, 27%, 29%, 29.5%).

[0012] In the above-mentioned iron-based amorphous soft magnetic alloy, as a preferred embodiment, 9% < b < 19% (such as 10%, 12%, 14%, 15%, 16%, 17%, 18%).

[0013] In the present invention, the Co content affects the cost and the DC saturation resistance ability, while the Ni content affects the linearity. Therefore, by further limiting b + c within the above range, an iron-based amorphous soft magnetic alloy with both low cost and high DC saturation resistance and high linearity can be obtained. Currently, the price of nickel is much lower than that of cobalt. Therefore, considering the cost, in the present invention, low-cost Ni is used to replace Co to control the minimum addition amount of Co. By further limiting b + c within the above range, it can be ensured that Co elements are not replaced by excessive Ni elements, thus avoiding the reduction of the DC resistance ability. At the same time, controlling the excessive addition of Co elements is for two reasons. On the one hand, it is to control the cost. On the other hand, the large addition of a single component will reduce the entropy value of the alloy, thereby reducing the anisotropy and affecting the saturation resistance ability.

[0014] In the above iron-based amorphous soft magnetic alloy, as a preferred embodiment, the magnetic permeability of the iron-based amorphous soft magnetic alloy is 1000 - 2000 (such as 1200, 1400, 1500, 1700, 1900), the attenuation degree within the magnetic field range of 0 - 600 A / m is ≤ 2%, and the saturation DC magnetic field strength can reach up to 800 A / m.

[0015] The second aspect of the present invention provides a magnetic core wound by the above iron-based amorphous soft magnetic alloy.

[0016] The third aspect of the present invention provides a preparation method of the above iron-based amorphous soft magnetic alloy, including:

[0017] Step 1: Prepare alloy raw materials according to the chemical composition ratio of the above iron-based amorphous soft magnetic alloy, and then melt the alloy raw materials to obtain molten steel;

[0018] Step 2: Perform strip casting and rapid quenching treatment on the above molten steel to obtain a strip, and then cut and wind the strip into a magnetic core;

[0019] Step 3: Heat-treat the above magnetic core under magnetic field conditions to obtain an iron-based amorphous soft magnetic alloy.

[0020] In the present invention, a strip that is macroscopically isotropic is obtained through strip casting and rapid quenching treatment. As a basic strip, it can be simply batch-processed (single-strip winding to obtain a magnetic core). Compared with single-strip processing (special processing to obtain target performance), the efficiency can be greatly improved. The chemical composition of the iron-based amorphous soft magnetic alloy in the present invention determines the intrinsic atomic cluster anisotropy of the alloy. However, since the atomic clusters are randomly distributed inside the alloy, the strip obtained through strip casting and rapid quenching treatment is macroscopically isotropic. By further heat-treating under magnetic field, the anisotropy of the atomic clusters inside the alloy is arranged, so that the obtained alloy is macroscopically anisotropic. Therefore, for the successful preparation of an iron-based amorphous soft magnetic alloy, both the chemical composition and the magnetic field heat treatment are indispensable.

[0021] In the above preparation method, as a preferred embodiment, in the first step, the temperature of the smelting is 1100 - 1300 °C (such as 1120 °C, 1150 °C, 1200 °C, 1250 °C, 1280 °C), and the time is 60 min - 180 min (such as 70 min, 90 min, 100 min, 120 min, 150 min).

[0022] In the above preparation method, as a preferred embodiment, in the second step, in the rapid quenching by spinning, the spinning rate is 25 - 30 m / s (such as 26 m / s, 27 m / s, 28 m / s, 29 m / s); preferably, the thickness of the strip is 20 - 30 μm (such as 22 μm, 24 μm, 25 μm, 26 μm, 28 μm); preferably, the specifications of the magnetic core are OD (outer diameter) 20 - 30 mm (such as 22 mm, 24 mm, 25 mm, 26 mm, 28 mm) × ID (inner diameter) 10 - 15 mm (such as 11 mm, 12 mm, 13 mm, 14 mm) × H (height) 5 - 15 mm (such as 6 mm, 8 mm, 10 mm, 12 mm, 14 mm).

[0023] In the above preparation method, as a preferred embodiment, in the third step, the heat treatment is carried out under vacuum conditions, inert gas or hydrogen reducing gas conditions; preferably, in the heat treatment, the heating temperature is 300 - 500 °C (such as 320 °C, 350 °C, 400 °C, 450 °C, 480 °C), and the holding time is 0.5 - 3 h (such as 0.8 h, 1 h, 1.5 h, 2 h, 2.5 h); preferably, the heating rate is 3 - 10 °C / min (such as 4 °C / min, 5 °C / min, 6 °C / min, 7 °C / min, 8 °C / min, 9 °C / min); preferably, in the heat treatment, after the holding is completed, cooling is carried out, and the cooling rate is 1 - 5 °C / min (such as 2 °C / min, 3 °C / min, 4 °C / min, 4.5 °C / min).

[0024] In the present invention, since rapid heating often causes the latent heat of phase change released inside the magnetic core to lead to too high local temperature, the heating rate is limited to 3 - 10 °C / min; in order to prevent the internal stress generated by cooling, the cooling rate is limited to 1 - 5 °C / min.

[0025] In the above preparation method, as a preferred embodiment, in the third step, a magnetic field is applied along the axial direction of the magnetic core; preferably, the magnetic field intensity is 300 - 1200 Gs (such as 400 Gs, 600 Gs, 800 Gs, 1000 Gs).

[0026] The fourth aspect of the present invention provides an application of the above-mentioned iron-based amorphous soft magnetic alloy in a high-precision current transformer or a DC-resistant CT.

[0027] The present invention has the following beneficial effects compared with the prior art:

[0028] (1) The magnetic permeability of the iron-based amorphous soft magnetic alloy prepared by the present invention ranges from 1000 to 2000, and the magnetic permeability can be effectively regulated by adjusting the Co and Ni contents.

[0029] (2) The attenuation degree of the iron-based amorphous soft magnetic alloy prepared by the present invention is ≤2% in the magnetic field range of 0 - 600 A / m, and the linearity of the alloy is effectively improved.

[0030] (3) The saturation DC magnetic field strength of the iron-based amorphous soft magnetic alloy prepared by the present invention can reach up to 800 A / m at most, effectively suppressing DC saturation. Description of the Drawings

[0031] Figure 1 It is the static hysteresis loop and basic magnetization curve of the iron-based amorphous soft magnetic alloy prepared in Example 1 of the present invention.

[0032] Figure 2 It is the basic magnetization curve and magnetic permeability curve of the iron-based amorphous soft magnetic alloy prepared in Example 1 of the present invention.

[0033] Figure 3 It is the static hysteresis loop and basic magnetization curve of the iron-based amorphous soft magnetic alloy prepared in Example 2 of the present invention.

[0034] Figure 4 It is the basic magnetization curve and magnetic permeability curve of the iron-based amorphous soft magnetic alloy prepared in Example 2 of the present invention.

[0035] Figure 5 It is the XRD pattern of the iron-based amorphous soft magnetic alloy prepared in Example 1 of the present invention.

[0036] Figure 6 It is the static hysteresis loop and basic magnetization curve of the iron-based amorphous soft magnetic alloy prepared in Example 3 of the present invention.

[0037] Figure 7 It is the basic magnetization curve and magnetic permeability curve of the iron-based amorphous soft magnetic alloy prepared in Example 3 of the present invention.

[0038] Figure 8 It is the static hysteresis loop and basic magnetization curve of the iron-based amorphous soft magnetic alloy prepared in Example 4 of the present invention.

[0039] Figure 9 It is the basic magnetization curve and magnetic permeability curve of the iron-based amorphous soft magnetic alloy prepared in Example 4 of the present invention.

[0040] Figure 10 The static hysteresis loop and basic magnetization curve of the iron-based amorphous soft magnetic alloy prepared in Comparative Example 1 of the present invention.

[0041] Figure 11 The basic magnetization curve and permeability curve of the iron-based amorphous soft magnetic alloy prepared in Comparative Example 2 of the present invention.

[0042] Figure 12 The basic magnetization curve and permeability curve of the iron-based amorphous soft magnetic alloy prepared in Comparative Example 3 of the present invention.

[0043] Figure 13 The basic magnetization curve and permeability curve of the iron-based amorphous soft magnetic alloy prepared in Comparative Example 4 of the present invention. Detailed implementation manners

[0044] The iron-based amorphous soft magnetic alloy and its preparation method of the present invention will be described below with reference to the accompanying drawings and embodiments. It should be understood that these embodiments are only used to explain the present invention and not to limit the scope of the present invention. It should be understood that after reading the content of the present invention, those skilled in the art make various changes and modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims of this application.

[0045] In the test methods in the following embodiments, unless otherwise specified, they are all conventional methods, and can be carried out according to the techniques or conditions described in the literature in the art or according to the product specifications. The raw materials described in the following embodiments can all be obtained from public commercial channels.

[0046] The present invention will be further described in detail below with reference to specific embodiments.

[0047] Embodiment 1 A preparation method of an iron-based amorphous soft magnetic alloy, comprising:

[0048] Step 1. According to the chemical composition of the iron-based amorphous soft magnetic alloy: Fe a Co b Ni c Si d B e , where a, b, c, d, and e respectively represent the weight percentage contents of the corresponding elements, specifically: a = 68%, b = 11%, c = 10.5%, d = 8%, e = 2.5%. Prepare alloy raw materials, and then melt the alloy raw materials. The melting temperature is 1150°C, and the melting time is 1 h to obtain molten steel. Use a direct reading spectrometer to measure the composition of the molten steel, and control the content deviation of various elements in the molten steel from the corresponding component content of the designed iron-based amorphous soft magnetic alloy to be less than 0.1% (based on weight ratio).

[0049] Step 2: Subject the above molten steel to strip casting and rapid quenching to obtain a strip. The strip casting rate is 26 m / s, and the thickness of the strip is 23 - 26 μm. Then, cut and wind the strip into a magnetic core with the specification of OD25mm × ID13mm × H5mm;

[0050] Step 3: Apply a magnetic field along the axial direction of the above magnetic core. The magnetic field intensity is 600 Gs, and heat treatment is carried out under the magnetic field condition. The specific heat treatment conditions are as follows: Heat up to 420 °C at a heating rate of 8 °C / min under nitrogen gas, hold for 90 min, and then cool down to 150 °C at a cooling rate of 3 °C / min and open the furnace door for forced air cooling to obtain an iron-based amorphous soft magnetic alloy (the XRD results are as Figure 5 shown, indicating that the alloy prepared in Example 1 is an amorphous structure).

[0051] The iron-based amorphous soft magnetic alloy prepared in Example 1 is tested using an MTAS-2010SD soft magnetic DC measurement device. The primary coil and the secondary coil are insulated copper wires, the coil turns ratio is 30:3, the measured magnetic field Hs is 1200 A / m, the selected measurement method is pulsed magnetic field measurement, the pulse frequency is 0.02 Hz, and the increment of the magnetic field measurement point is 0.8 A / m.

[0052] The size of the tested iron-based amorphous soft magnetic alloy is OD25mm × ID13mm × H5mm, the magnetic circuit length le of the magnetic ring is 60 mm, and the effective magnetic cross-sectional area is 25 mm 2 , and the weight is 11 g.

[0053] Figure 1 are the static magnetic hysteresis loop and the basic magnetization curve of the iron-based amorphous soft magnetic alloy prepared in Example 1 of the present invention; Figure 2 are the basic magnetization curve and the permeability curve of the iron-based amorphous soft magnetic alloy prepared in Example 1 of the present invention. The measurement results show that the saturation magnetic induction intensity of this alloy is 1.35 T, the residual magnetic induction intensity Br < 10 mT, the coercivity Hc is 3.3 A / m, the characteristic permeability is about 1700 (relative permeability), and the attenuation of the permeability in the range of magnetic field intensity from 0 to 600 A / m is < 2%, showing good linearity.

[0054] Example 2 A preparation method of an iron-based amorphous soft magnetic alloy, including:

[0055] Step 1: According to the chemical composition of the iron-based amorphous soft magnetic alloy: Fe a Co b Ni c Si d B e, where a, b, c, d, and e respectively represent the weight percentage contents of the corresponding components, specifically: a = 66%, b = 8.5%, c = 13.5%, d = 7.5%, e = 4.5%. Prepare the alloy raw materials, and then melt the alloy raw materials at a melting temperature of 1230 °C for 2.5 h to obtain molten steel. Measure the composition of the molten steel using a direct-reading spectrometer, and control the content deviation of various elements in the molten steel from the corresponding component content of the designed iron-based amorphous soft magnetic alloy to be less than 0.1% (based on weight ratio).

[0056] Step 2: Perform a spin-rapid quenching treatment on the above molten steel to obtain a strip. The spin rate is 25 m / s, and the strip thickness is 22 - 24 μm. Then cut and wind the strip into a magnetic core with a magnetic core specification of OD25mm × ID13mm × H5mm.

[0057] Step 3: Apply a magnetic field along the axial direction of the above magnetic core. The magnetic field intensity is 800 Gs, and perform heat treatment under the magnetic field condition. The specific heat treatment conditions are as follows: Heat up to 470 °C at a heating rate of 4 °C / min under nitrogen gas, hold for 105 min, and then cool down to 200 °C at a cooling rate of 2 °C / min to open the furnace door for forced cooling. After verification by XRD diffraction analysis, an iron-based amorphous soft magnetic alloy is obtained.

[0058] The iron-based amorphous soft magnetic alloy prepared in Example 2 is tested using an MTAS-2010SD soft magnetic DC measurement device. The primary coil and the secondary coil are insulated copper wires, the coil turn ratio is 40:3, the measured magnetic field Hs is 2000 A / m, the selected measurement method is pulsed magnetic field measurement, the pulse frequency is 0.02 Hz, and the magnetic field measurement point increment is 0.8 A / m.

[0059] The size of the tested iron-based amorphous soft magnetic alloy is OD25mm × ID13mm × H5mm, the magnetic circuit length le of the magnetic ring is 60 mm, and the effective magnetic cross-sectional area is 25 mm 2 , and the weight is 11 g.

[0060] Figure 3 This is the static hysteresis loop and the basic magnetization curve of the iron-based amorphous soft magnetic alloy prepared in Example 2 of the present invention. Figure 4 This is the basic magnetization curve and the permeability curve of the iron-based amorphous soft magnetic alloy prepared in Example 2 of the present invention. The measurement results show that the saturation magnetic induction intensity of this alloy is 1.33 T, the remanent magnetic induction intensity Br < 10 mT, the coercivity Hc is 0.84 A / m, and the coercivity is significantly reduced compared with Example 1. Among them, the characteristic permeability is about 1500 (relative permeability), and the attenuation of the permeability in the range of magnetic field intensity from 0 to 650 A / m is < 2%, and the linearity is further improved.

[0061] Example 3 A preparation method of an iron-based amorphous soft magnetic alloy, comprising:

[0062] Step 1: According to the chemical composition of the iron-based amorphous soft magnetic alloy: Fe a Co b Ni c Si d B e , where a, b, c, d, and e respectively represent the weight percentage contents of the corresponding components. Specifically: a = 60%, b = 18%, c = 11%, d = 9%, e = 2%. Prepare the alloy raw materials, and then melt the alloy raw materials. The melting temperature is 1195°C, and the melting time is 1.5 h to obtain molten steel. Use a direct-reading spectrometer to measure the composition of the molten steel, and control the content deviation of various elements in the molten steel from the corresponding component content of the designed iron-based amorphous soft magnetic alloy to be less than 0.1% (based on weight ratio).

[0063] Step 2: Perform a strip casting and rapid quenching treatment on the above molten steel to obtain a strip. The strip casting rate is 28 m / s, and the strip thickness is 21 - 24 μm. Then cut and wind the strip into a magnetic core. The magnetic core specifications are OD25mm × ID13mm × H5mm.

[0064] Step 3: Apply a magnetic field along the axial direction of the magnetic core. The magnetic field strength is 500 Gs, and perform heat treatment under the magnetic field condition. The specific heat treatment conditions are: heat up to 435°C at a heating rate of 4°C / min under nitrogen gas, hold for 55 min, and then cool down to 200°C at a cooling rate of 2°C / min and open the furnace door for forced cooling. After verification by XRD diffraction analysis, an iron-based amorphous soft magnetic alloy is obtained.

[0065] The iron-based amorphous soft magnetic alloy prepared in Example 3 is tested using an MTAS-2010SD soft magnetic DC measurement device. The primary coil and the secondary coil are insulated copper wires, and the coil turn ratio is 35:3. The measured magnetic field Hs is 2000 A / m, the selected measurement method is pulsed magnetic field measurement, the pulse frequency is 0.02 Hz, and the magnetic field measurement point increment is 0.8 A / m.

[0066] The size of the tested iron-based amorphous soft magnetic alloy is OD25mm × ID13mm × H5mm, the magnetic circuit length le of the magnetic ring is 60 mm, and the effective magnetic cross-sectional area is 25 mm 2 , and the weight is 10.8 g.

[0067] Figure 6 This is the static magnetic hysteresis loop and the basic magnetization curve of the iron-based amorphous soft magnetic alloy prepared in Example 3 of the present invention. Figure 7This is the basic magnetization curve and permeability curve of the iron-based amorphous soft magnetic alloy prepared in Example 3 of the present invention. The measurement results show that the saturation magnetic induction intensity of this alloy is 1.28 T. Due to the relatively low Fe content, the saturation magnetic induction intensity is relatively low. The remanent magnetic induction intensity Br is 20 mT, and the coercivity Hc is 3.35 A / m. Among them, the characteristic permeability is about 1500 (relative permeability), which can meet the requirements of anti-DC performance.

[0068] Example 4 A preparation method of an iron-based amorphous soft magnetic alloy, comprising:

[0069] Step 1. According to the chemical composition of the iron-based amorphous soft magnetic alloy: Fe a Co b Ni c Si d B e , where a, b, c, d, and e respectively represent the weight percentage contents of the corresponding components. Specifically: a = 68%, b = 6%, c = 15%, d = 7.5%, e = 3.5%. Prepare the alloy raw materials, and then melt the alloy raw materials. The melting temperature is 1260 °C, and the melting time is 2.5 h to obtain molten steel. Use a direct-reading spectrometer to measure the composition of the molten steel, and control the content deviation of various elements in the molten steel from the corresponding component content of the designed iron-based amorphous soft magnetic alloy to be less than 0.1% (based on weight ratio).

[0070] Step 2. Perform a spinning and rapid quenching treatment on the above molten steel to obtain a strip. The spinning rate is 29 m / s, and the strip thickness is 23 - 26 μm. Then cut and wind the strip into a magnetic core, and the magnetic core specifications are OD25 mm × ID13 mm × H5 mm.

[0071] Step 3. Apply a magnetic field along the axial direction of the magnetic core. The magnetic field intensity is 1100 Gs, and perform heat treatment under the magnetic field condition. The specific heat treatment conditions are: heat up to 435 °C at a heating rate of 8 °C / min under nitrogen gas, hold for 35 min, and then cool down to 200 °C at a cooling rate of 3.5 °C / min and open the furnace door for forced cooling. After verification by XRD diffraction analysis, an iron-based amorphous soft magnetic alloy is obtained.

[0072] The iron-based amorphous soft magnetic alloy prepared in Example 4 is tested using an MTAS-2010SD soft magnetic DC measurement device. The primary coil and the secondary coil are insulated copper wires, and the coil turns ratio is 35:3. The measured magnetic field Hs is 2000 A / m. The selected measurement method is pulsed magnetic field measurement, the pulse frequency is 0.02 Hz, and the magnetic field measurement point increment is 0.8 A / m.

[0073] The size of the tested iron-based amorphous soft magnetic alloy is OD25 mm × ID13 mm × H5 mm. The magnetic circuit length le of the magnetic ring is 60 mm, and the effective magnetic cross-sectional area is 25 mm2 , with a weight of 10.5 g.

[0074] Figure 8 This is the static hysteresis loop and the basic magnetization curve of the iron-based amorphous soft magnetic alloy prepared in Example 4 of the present invention. Figure 9 This is the basic magnetization curve and the permeability curve of the iron-based amorphous soft magnetic alloy prepared in Example 4 of the present invention. The measurement results show that the saturation magnetic induction intensity of this alloy is 1.14 T. Due to the relatively high Ni content, the saturation magnetic induction intensity is relatively low. The remanent magnetic induction intensity Br is 8 mT, and the coercive force Hc is 1.04 A / m. Among them, the characteristic permeability is about 1100 (relative permeability), which can meet the requirements of DC resistance performance, but the linearity is worse than that of Example 1.

[0075] Comparative Example 1 A preparation method of an iron-based amorphous soft magnetic alloy, comprising:

[0076] Step 1. According to the chemical composition of the iron-based amorphous soft magnetic alloy: Fe a Co b Ni c Si d B e , where a, b, c, d, and e respectively represent the weight percentage contents of the corresponding elements, specifically: a = 70%, b = 6%, c = 13.5%, d = 8%, e = 2.5%. Prepare the alloy raw materials, and then melt the alloy raw materials. The melting temperature is 1130 °C, and the melting time is 1.5 h to obtain molten steel. Use a direct-reading spectrometer to measure the composition of the molten steel, and control the content deviation of various elements in the molten steel from the corresponding component content of the designed iron-based amorphous soft magnetic alloy to be less than 0.1% (based on weight ratio).

[0077] Step 2. Perform a spin-rapid quenching treatment on the above molten steel to obtain a strip. The spin rate is 26 m / s, and the strip thickness is 22 - 25 μm. Then cut and wind the strip into a magnetic core. The magnetic core specifications are OD25 mm × ID13 mm × H5 mm;

[0078] Step 3. Apply a magnetic field along the axial direction of the magnetic core. The magnetic field intensity is 600 Gs, and perform heat treatment under the magnetic field condition. The specific heat treatment conditions are: heat up to 405 °C at a heating rate of 8 °C / min under nitrogen gas, hold for 60 min, and then cool down to 150 °C at a cooling rate of 3 °C / min to open the furnace door for forced cooling. After verification by XRD diffraction analysis, an iron-based amorphous soft magnetic alloy is obtained.

[0079] The sample was tested using an MTAS-2010SD soft magnetic DC measurement device. The primary coil and the secondary coil are made of insulated copper wire, the coil turns ratio is 45:3, the measured magnetic field Hs is 2500 A / m, the selected measurement method is pulsed magnetic field measurement, the pulse frequency is 0.02 Hz, and the increment of the magnetic field measurement point is 0.8 A / m.

[0080] The size of the test sample is OD25mm×ID13mm×H5mm, the magnetic circuit length le of the magnetic ring is 60mm, and the effective magnetic cross-sectional area is 25mm 2 , and the weight is 11g.

[0081] Figure 10 This is the static hysteresis loop and the basic magnetization curve of the iron-based amorphous soft magnetic alloy prepared in Comparative Example 1 of the present invention. The measurement results show that the saturation magnetic induction intensity of this alloy is 1.71 T, and the coercivity Hc is 301 A / m. The coercivity is relatively high and cannot meet the actual use requirements.

[0082] Comparative Example 2 A preparation method of an iron-based amorphous soft magnetic alloy, comprising:

[0083] Step 1. According to the chemical composition of the iron-based amorphous soft magnetic alloy: Fe a Co b Ni c Si d B e , where a, b, c, d, and e respectively represent the weight percentage contents of the corresponding elements. Specifically: a = 58%, b = 18%, c = 13.5%, d = 8%, e = 2.5%. Prepare the alloy raw materials, and then melt the alloy raw materials. The melting temperature is 1210 °C, and the melting time is 1 h to obtain molten steel. Use a direct reading spectrometer to measure the composition of the molten steel, and control the content deviation of various elements in the molten steel from the corresponding component content of the designed iron-based amorphous soft magnetic alloy to be less than 0.1% (based on weight ratio).

[0084] Step 2. Perform a spin-rapid quenching treatment on the above molten steel to obtain a strip. The spin rate is 25 m / s, and the thickness of the strip is 22 - 25 μm. Then cut and wind the strip into a magnetic core. The specifications of the magnetic core are OD25mm×ID13mm×H5mm;

[0085] Step 3. Apply a magnetic field along the axial direction of the magnetic core. The magnetic field intensity is 600 Gs, and perform heat treatment under the magnetic field condition. The specific heat treatment conditions are: heat up to 395 °C at a heating rate of 8 °C / min under nitrogen gas, hold for 120 min, and then cool down to 150 °C at a cooling rate of 3 °C / min and open the furnace door for forced cooling. After verification by XRD diffraction analysis, an iron-based amorphous soft magnetic alloy is obtained.

[0086] The sample was tested using an MTAS-2010SD soft magnetic DC measurement device. The primary coil and the secondary coil are made of insulated copper wire, the coil turn ratio is 40:3, the measured magnetic field Hs is 2000 A / m, the selected measurement method is pulsed magnetic field measurement, the pulse frequency is 0.02 Hz, and the increment of the magnetic field measurement point is 0.8 A / m.

[0087] The sample size is OD25mm × ID13mm × H5mm, the magnetic path length le of the magnetic ring is 60mm, and the effective magnetic cross-sectional area is 25mm 2 , and the weight is 11.5 g.

[0088] Figure 11 This is the basic magnetization curve and permeability curve of the iron-based amorphous soft magnetic alloy prepared in Comparative Example 2 of the present invention. The measurement results show that the initial permeability of the alloy is 2400 (relative permeability), and the permeability decays significantly as the magnetic field strength increases, with poor linearity and unable to meet the actual use requirements.

[0089] Comparative Example 3 A preparation method of an iron-based amorphous soft magnetic alloy, comprising:

[0090] Step 1. According to the chemical composition of the iron-based amorphous soft magnetic alloy: Fe a Co b Ni c Si d B e , where a, b, c, d, and e respectively represent the weight percentage contents of the corresponding elements. Specifically: a = 73.5%, b = 11%, c = 5%, d = 8%, e = 2.5%. Prepare the alloy raw materials, and then melt the alloy raw materials. The melting temperature is 1225 °C, and the melting time is 2 h to obtain molten steel. Use a direct-reading spectrometer to measure the composition of the molten steel, and control the content deviation of various elements in the molten steel from the corresponding component content of the designed iron-based amorphous soft magnetic alloy to be less than 0.1% (based on weight ratio).

[0091] Step 2. Perform a spinning and rapid quenching treatment on the above molten steel to obtain a strip. The spinning rate is 27 m / s, and the strip thickness is 23 - 26 μm. Then cut and wind the strip into a magnetic core, and the magnetic core specifications are OD25mm × ID13mm × H5mm;

[0092] Step 3. Apply a magnetic field along the axial direction of the magnetic core. The magnetic field strength is 600 Gs, and perform heat treatment under the magnetic field condition. The specific heat treatment conditions are: heat up to 355 °C at a heating rate of 8 °C / min under nitrogen gas, hold for 120 min, and then cool down to 150 °C at a cooling rate of 3 °C / min and open the furnace door for forced cooling. After verification by XRD diffraction analysis, an iron-based amorphous soft magnetic alloy is obtained.

[0093] The sample was tested using an MTAS-2010SD soft magnetic DC measurement device. The primary coil and the secondary coil are insulated copper wires, the coil turn ratio is 30:3, the measured magnetic field Hs is 2000 A / m, the selected measurement method is pulsed magnetic field measurement, the pulse frequency is 0.02 Hz, and the increment of the magnetic field measurement point is 0.8 A / m.

[0094] The size of the test sample is OD25mm×ID13mm×H5mm, the magnetic circuit length le of the magnetic ring is 60mm, and the effective magnetic cross-sectional area is 25mm 2 , and the weight is 11 g.

[0095] Figure 12 This is the basic magnetization curve and permeability curve of the iron-based amorphous soft magnetic alloy prepared in Comparative Example 3 of the present invention. The measurement results show that the initial permeability of this alloy is 1500 (relative permeability), and the permeability fluctuates significantly when the magnetic field strength increases, with poor linearity and unable to meet the actual use requirements.

[0096] Comparative Example 4 A preparation method of an iron-based amorphous soft magnetic alloy, comprising:

[0097] Step 1. According to the chemical composition of the iron-based amorphous soft magnetic alloy: Fe a Co b Ni c Si d B e , where a, b, c, d, and e respectively represent the weight percentage contents of the corresponding elements, specifically: a = 59%, b = 11%, c = 19.5%, d = 8%, e = 2.5%. Prepare the alloy raw materials, and then melt the alloy raw materials. The melting temperature is 1250 °C, and the melting time is 2.5 h to obtain molten steel. Use a direct-reading spectrometer to measure the composition of the molten steel, and control the content deviation of various elements in the molten steel from the corresponding component content of the designed iron-based amorphous soft magnetic alloy to be less than 0.1% (based on weight ratio).

[0098] Step 2. Perform a spinning and rapid quenching treatment on the above molten steel to obtain a strip. The spinning rate is 28 m / s, and the strip thickness is 24 - 27 μm. Then cut and wind the strip into a magnetic core, and the magnetic core specifications are OD25mm×ID13mm×H5mm;

[0099] Step 3. Apply a magnetic field along the axial direction of the magnetic core. The magnetic field strength is 600 Gs, and perform heat treatment under the magnetic field condition. The specific heat treatment conditions are: heat up to 425 °C at a heating rate of 8 °C / min under nitrogen gas, hold for 75 min, and then cool down to 150 °C at a cooling rate of 3 °C / min and open the furnace door for forced cooling. The iron-based amorphous soft magnetic alloy is obtained through XRD diffraction analysis verification.

[0100] The sample was tested using an MTAS-2010SD soft magnetic DC measurement device. The primary coil and the secondary coil are made of insulated copper wire, the coil turns ratio is 25:3, the measured magnetic field Hs is 1500 A / m, the selected measurement method is pulsed magnetic field measurement, the pulse frequency is 0.02 Hz, and the increment of the magnetic field measurement point is 0.8 A / m.

[0101] The size of the test sample is OD25mm×ID13mm×H5mm, the magnetic circuit length le of the magnetic ring is 60mm, and the effective magnetic cross-sectional area is 25mm 2 , and the weight is 10.5 g.

[0102] Figure 13 This is the basic magnetization curve and permeability curve of the iron-based amorphous soft magnetic alloy prepared in Comparative Example 4 of the present invention. The measurement results show that the initial permeability of the alloy is 1500 (relative permeability), the permeability fluctuates greatly when the magnetic field strength increases, it cannot maintain a constant permeability, the linearity is poor, and it cannot meet the actual use requirements.

[0103] Performance Test

[0104] The magnetic property test part of the present invention was tested according to the principle described in the GB 3657-83 method for measuring the DC magnetic properties of soft magnetic alloys. The device used is an MTAS-2010SD soft magnetic DC measurement device, and the primary coil and the secondary coil are made of insulated copper wire.

[0105] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention are within the scope of the claims of the present invention awaiting approval.

Claims

1. An iron-based amorphous soft magnetic alloy, characterized in that, The chemical composition of the iron-based amorphous soft magnetic alloy is: Fe a Co b Ni c Si d B e M f , where a, b, c, d, e, and f respectively represent the weight percentage contents of the corresponding elements; 5% < b < 20%, 10% < c < 14%, 7% < d < 10%, 0 < e < 5%, 0 ≤ f < 1%, the balance is a, and 20% < b + c < 23%; M is one or more of Cr, Mo, Mn, V, and Al.

2. The iron-based amorphous soft magnetic alloy according to claim 1, characterized in that, The chemical composition of the iron-based amorphous soft magnetic alloy is: Fe a Co b Ni c Si d B e , where a, b, c, d, and e respectively represent the weight percentage contents of the corresponding elements, 10% < c < 14%, 7% < d < 10%, 0 < e < 5%, the balance is a, and 20% < b + c < 23%; 9% < b < 19%.

3. The iron-based amorphous soft magnetic alloy according to claim 1 or 2, characterized in that, the magnetic permeability of the iron-based amorphous soft magnetic alloy is 1000 - 2000, the attenuation degree is ≤ 2% within the magnetic field range of 0 - 600 A / m, and the saturation direct current magnetic field strength can reach up to 800 A / m at most.

4. A magnetic core, characterized in that, the magnetic core is wound by the iron-based amorphous soft magnetic alloy according to any one of claims 1 - 3.

5. A preparation method of an iron-based amorphous soft magnetic alloy, characterized in that, comprising: Step 1: Prepare alloy raw materials according to the chemical composition ratio of the iron-based amorphous soft magnetic alloy according to any one of claims 1 - 3, and then melt the alloy raw materials to obtain molten steel; Step 2: Perform a spinning and rapid quenching treatment on the molten steel to obtain a strip, and then cut and wind the strip into a magnetic core; Step 3: Heat-treat the magnetic core under magnetic field conditions to obtain an iron-based amorphous soft magnetic alloy; In step 3, a magnetic field is applied along the axial direction of the magnetic core.

6. The preparation method according to claim 5, characterized in that, in step 1, the temperature of the melting is 1100 - 1300 °C, and the time is 60 min - 180 min.

7. The preparation method according to claim 5, characterized in that, in step 2, during the spinning and rapid quenching, the spinning rate is 25 - 30 m / s.

8. The preparation method according to claim 5, characterized in that, the thickness of the strip is 20 - 30 μm; the specifications of the magnetic core are OD 20 - 30 mm × ID 10 - 15 mm × H5 - 15 mm.

9. The preparation method according to claim 5, characterized in that, in step 3, the heat treatment is carried out under vacuum conditions, inert gas or hydrogen reduction gas conditions.

10. The preparation method according to claim 5, characterized in that, in step 3, during the heat treatment, the heating temperature is 300 - 500 °C, the heat preservation time is 0.5 - 3 h; the heating rate is 3 - 10 °C / min; during the heat treatment, cooling is carried out after the heat preservation ends, and the cooling rate is 1 - 5 °C / min.

11. The preparation method according to claim 5, characterized in that, the intensity of the magnetic field is 300 - 1200 Gs.

12. Application of the iron-based amorphous soft magnetic alloy according to any one of claims 1 - 3 in a high-precision current transformer or a DC-resistant CT.

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